.jd_main {
  height: 50rem;
  min-width: 300px;
  max-width: 600px;
  position: relative;
  margin: 0 auto;
}
.jd_main .jd_header {
  position: fixed;
  left: 0;
  top: 0;
  height: 40px;
  width: 100%;
}
.jd_main .jd_header .header_box {
  height: 40px;
  min-width: 300px;
  max-width: 600px;
  background-color: red;
  position: relative;
  margin: 0 auto;
}
.jd_main .jd_header .header_box .icon_login {
  position: absolute;
  background-position: 0 -103px;
  width: 60px;
  height: 36px;
  display: block;
  top: 4px;
  left: 10px;
}
.jd_main .jd_header .header_box form {
  width: 100%;
  height: 40px;
  padding-left: 75px;
  padding-right: 55px;
  position: relative;
}
.jd_main .jd_header .header_box form .icon_search {
  position: absolute;
  background-position: -60px -109px;
  width: 20px;
  height: 20px;
  display: block;
  top: 10px;
  left: 85px;
}
.jd_main .jd_header .header_box form input {
  width: 100%;
  height: 30px;
  border-radius: 15px;
  margin-top: 5px;
  padding-left: 40px;
}
.jd_main .jd_header .header_box .login {
  position: absolute;
  width: 50px;
  height: 40px;
  top: 0;
  right: 0;
  color: #ffffff;
  display: block;
  text-align: center;
  line-height: 40px;
  font-size: 15px;
}
.jd_main .jd_banner {
  width: 100%;
  overflow: hidden;
  position: relative;
}
.jd_main .jd_banner ul {
  width: 100%;
  float: left;
  display: block;
}
.jd_nav {
  height: 169px;
  width: 100%;
  border-bottom: 1px solid #c0c0c0;
  padding: 0 3.125%;
}
.jd_nav ul {
  width: 100%;
  margin-top: 10px;
}
.jd_nav ul li {
  width: 25%;
  height: 69px;
  float: left;
}
.jd_nav ul li a {
  display: block;
  width: 100%;
  height: 100%;
  text-align: center;
}
.jd_nav ul li a img {
  height: 40px;
  width: 40px;
  display: block;
  margin: 0 auto;
}
.jd_nav ul li a img p {
  font-size: 12px;
  color: #666;
}
[class^="icon_"] {
  background: url("../images/sprites.png") no-repeat;
  background-size: 200px 200px;
}
